Authors:

Ankur Bordoloi(University of California Berkeley)

Evan Variano(University of California Berkeley)

Small axisymmetric particles are known to show shape dependence in their
rotational kinematics in homogenous isotropic turbulence. For example, Byron
et al. (2015) demonstrated that, rod-shaped particles rotate very
differently compared to disc-shaped ones. This motivates us to extend this
understanding to finite-sized particles ($\sim$ Taylor microscale)
by examining their rotation and alignment. We have overcome the experimental
challenges that have heretofore prevented the simultaneous measurement of
orientation and rotation of large particles. We present this method and
report results for large cylinders from 2D3C stereoscopic PIV data. These
preliminary results show that there is equipartition of particle enstrophy
into spinning about each of the particle's local axes. In other words, there
is no preference for rotation about a particle's symmetry axis. Time
permitting, effects of size on rotation for Taylor microscale particles will
also be discussed.

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2015.DFD.G3.7